A heald frame for loom is used for suspending a number of healds through which warps pass and being subjected to high-speed shedding motion on the loom so as to produce fabrics. The heald frme is required to be made of a material that has sufficient rigidity and strength so that it is not deformed or broken even if it undergoes rapid motion while being subjected to a tension of the number of warps. For this reason, fragile materials such as wood are not suitable for use as the material of heald frame although they are lightweight. Most of the conventionally employed heald frames are therefore made of metallic materials such as iron, stainless steel, aluminum alloys, and magnesium alloys.
Recent advances in the technology of high-speed weaving using, e.g., air-jet looms, have been remarkable, and the demand for moving the healds at higher speeds is continuously growing. Heavy metallic materials are limited in improving the speed, the active efforts are underway to find materials that are lighter in weight and which have greater strength and rigidty than metallic materials.
One approach toward this end is to use carbon fiber-reinforced plastics (hereinafter referred as CFRP) having high levels of specific strength and specific rigidity, and it has been proposed in Japanese patent application (OPI) No. 43457/72 to employ CFRP in a heald frame which supports healds or droppers or a dropper rod. (The term "OPI" as used herein means an "unexamined published application".) This patent, however, does not at all take into consideration the employment of CFRP in an outer stay of heald frame. The heald frame shown in this patent is one formed by laminating and adhering carbon fibers or a composite material thereof in the longitudinal direction. However, this proposed idea is not completely satisfactory because the strength potential of carbon fibers or composite material thereof is not exploited to the fullest extent.